Question

Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 g mol⁻¹) is
(a) twice that in 60 g carbon
(b) 6.023 x 10²²
(c) half that in 8 g He
(d) 558.5 x 6.023 x 10²³

Answer 1

it would be (a)twice than in 60 g carbon

first calculate no. of moles:- 558.5/55.85

=10

1 mole contains 6.023×10^23 atoms

hence 10 mole would contain:- 10×6.022×10^24

no. of moles of carbon=60/12=5

hence number of atoms =5×6.023×10^23

hence, a is the required expression.